The overall objective of this research is to study the control of the peripheral circulation in abnormal cardiovascular states. The research projects have been organized under four headings as follows: 1. Regulation of the peripheral circulation in hypertensive states. 2. Regulation of the peripheral circulation in cardiac disease. 3. Regulation of the circulation in peripheral vascular disease. 4. Physiology, pathophysiology and pharmacology of the coronary circulation. The research includes studies on isolated vessels, animal models, normal human subjects and patients. We are concerned with the neurogenic control of blood vessels; the contribution of humoral factors such as vasopressin and prostaglandins; the role of sodium; the effect of therapeutic interventions such as digitalis, morphine, diuretics, physical training, sympathectomy and alteration of blood lipids; and with electrophysiological alterations in vascular smooth muscle in these abnormal states. The program represents an interdisciplinary effort at intra and inter-departmental levels including both clinical and basic science departments. The support provides resources to be shared by all participating investigators as well as support for research needs of each investigator. Significant steps have been taken in each of the areas of research described above and the on-going research program has provided the opportunity for the anticipated interdisciplinary interaction including both clinical and basic science departments. The program has been expanded this year with additional new investigators to explore areas such as: the regulation of segmental myocardial performance after ischemia; the regulation of SA node automaticity; the basic mechanisms involved in the behavior of vascular smooth muscle; the development of a model for the study of deformation pattern and stress analysis of the left ventricle; the study of the biosynthesis of neurotransmitters in heart and blood vessels in models of heart failure.